Comparison of epinephrine vs lipid rescue to treat severe local anesthetic toxicity - an experimental study in piglets.

Objectives: Local anesthetic (LA) intoxication with severe hemodynamic compromise is a potential catastrophic event. Lipid resuscitation has been recommended for the treatment of LA-induced cardiac arrest. However, there are no data about effectiveness of Intralipid for the treatment of severe cardiovascular compromise prior to cardiac arrest. Aim of this study was to compare effectiveness of epinephrine and Intralipid for the treatment of severe hemodynamic compromise owing to bupivacaine intoxication.
Methods:   Piglets were anesthetized with sevoflurane, intubated, and ventilated. Bupivacaine was infused with a syringe driver via a central venous catheter at a rate of 1 mg·kg(-1) ·min(-1) until invasively measured mean arterial pressure (MAP) dropped to 50% of the initial value. Bupivacaine infusion was then stopped, and epinephrine 3 μg·kg(-1) (group 1), Intralipid(®) 20% 2 ml·kg(-1) (group 2), or Intralipid 20% 4 ml·kg(-1) (group 3) was immediately administered. Survival, hemodynamic course, and ET(CO2) were recorded.
Results:   Twenty-one piglets (3 × 7), with median age of 26 days (19-43) and weighing 4.9 kg (4.3-5.8), were investigated. All animals in group 1 (100%) but only four of seven (57%) piglets in group 2 and group 3, respectively, survived. Normalization of hemodynamic parameters (HR, MAP) and ET(CO2) was fastest in group 1 with all piglets achieving HR and MAP values at or above baseline within 1 min.
Conclusion:   For the treatment of severe hemodynamic compromise owing to bupivacaine intoxication in piglets, first-line rescue with epinephrine was more effective than Intralipid with regard to survival as well as normalization of hemodynamic parameters and ET(CO2) .
(© 2011 Blackwell Publishing Ltd.)